He flew into Vancouver at the start of the second episode so he's likely not in the first (I say likely because they're also going to be shooting scenes at The Castro so I don't know if he could be slotted in later), but the activist he's playing was a huge deal in the San Francisco gay community as well as nationally (he was the first out gay man on the cover of Newsweek, was vocal about having AIDS--an anomaly for obvious reasons). It's an 8 hour miniseries and he's recurring, at any rate, and if the role is small it'll still wind up being an important one.